Frequencies of thalassemia in American blacks.

The frequency of thalassemia was determined in a group of 541 healthy adult black males. Individuals with decreased mean corpuscular hemoglobin (MCH) values were evaluated further with hemoglobin analysis, iron studies, and globin chain synthesis. Of the males screened, 13.4% had MCH levels below 27.0 pg, while 1.4% had heterozygous beta thalassemia, 2.3% had iron deficiency, and 5.7% had globin synthesis findings compatible with the diagnosis of alpha thalassemia trait (alpha thalassemia-1). This study suggests that thalassemia is one of the most frequent hematologically depictable abnormalities in American blacks.